Agitator for a washing machine

ABSTRACT

Agitator structure for variable washing action in a centerpost washing machine which comprises two similarly shaped agitators, one capable of being nested in and enclosed by the other. The inner agitator provides a relatively gentle washing action and the outer agitator, when placed over and driven by the inner agitator, provides regular washing action.

I United States Patent [151 3,641,791

Wine et al. 1 Feb. 15, 1972 [54] AGITATOR FOR A WASHING 2,974,510 3/1961 Gerhardt ..68/4

MACHINE P [72] Inventors: Robert R. Wine; Jerome G. Jacolnen, both Anmary g g g E g;

of Mansfi 61 (1, Ohio ttorneyenson an enz [73] Assignee: Westinghouse Electric Corporation, Pitt- [57] ABSTRACT Sburgh' Agitator structure for variable washing action in a centerpost [22] Filed: May 4, 1970 washing machine which comprises two similarly shaped agitators, one capable of being nested in and enclosed by the other. [2]] Appl 34465 The inner agitator provides a relatively gentle washing action [52] US. Cl ..68/4, 68/134 and the outer agitator, when placed over and driven by the llll- 06 1306f 39/ inner agitator, provides regular washing action. [58] Field of Search ..68/4, 134 [56] References Cited UNITED STATES PATENTS 3,027,742 4/1962 Nowicki ..68/134 x 5 Claims 3 Drawing gums o a 9 u o O o o goon PATENTEDFEB15 1912 3.641.791

SHEEI10F2 o o o o l o o o o o o o I I o o i I i o o 1 1 fr l l l 10 J I 14 l i I r l 1 f C l I A I I l I l l o i I o o o 0 0 o o o o r 0 o o o o o o I 0120 o o o o o :0 o o 0 o o 0 l i l o o o o o o o I l E\ J WITNESSES llr FIG 1 FNVENTORS a 52W Robert R. Wme & Jerome G. Jacobsen BYW/fl W2 ATTORNEY AGITATOR FOR A WASHING MACHINE BACKGROUND OF THE INVENTION This invention relates in general to centerpost agitator clothes washers and more particularly, to agitator structure for use therewith which provides either gentle washing action or regular washing action as desired.

It is desirable in a clothes washer to be able to wash various soiled fabrics in a manner best suited for the fabric such that delicate fabrics are washed relatively gently and heavier fabrics are washed relatively vigorously.

The well-known centerpost agitator clothes washer lends itself to various methods of providing the different washing actions desired. Thus, in the past, it has been accomplished by: changing the speed of the driving motor, i.e., shifting from a four-pole to a six-pole operation; shifting a two-speed clutch device, and using an agitator structure with radially adjustable vanes, i.e., U.S. Pat. No. 3,401,540.

A still further method of varying the washing action is to have an agitator structure and an enclosure therefor which either partially or completely encloses the agitator of one configuration for providing one washing action with another configuration which provides a different washing action. Exemplary of such agitators are US. Pat. Nos. 2,927,449, 2,974,510 and 2,974,511.

The present invention is concerned with agitator means for providing either a gentle washing action or a regular washing action in a manner which generally comes within this configuration.

SUMMARY Briefly, contrary to such prior art devices which provide a more gentle washing action by covering all or a portion of an inner agitator structure, the present invention includes two similarly shaped agitator structures having a centerpost extending from a generally convex base portion and a vane structure comprising a plurality of spiral ramps extending from the centerpost and integral at one of their ends with the base portion. One .of the agitator structures is substantially larger than the other and comprises a hollow casing capable of completely receiving the smaller structure therein in nesting relationship. The smaller agitator has a hollow centerpost with means therein for drivingly engaging the driving shaft of the washer, and, when used by itself provides gentle washing action. When regular washing action is desired, the larger agitator structure is placed over the smaller agitator in driving engagement therewith. The larger vane structure of the outer agitator produces a more vigorous and turbulent washing action.

DESCRIPTION OF THE DRAWINGS FIG. I is an exploded elevational view of the agitator structure of the present invention in a standard washer basket with portions broken away;

FIGv 2 is an exploded elevational view of the agitator drive means with portions broken away; and

FIG. 3 is a cross-sectional view in a plane at a right angle to the axis of rotation and passing through the drive means.

DESCRIPTION OF THE PREFERRED EMBODIMENT The agitator structure of the present invention is for use in a centerpost agitator washing machine of well-known construction and, as shown in FIG. 1, includes a standard washing basket or tub which generally during the agitation cycle is stationary, but during various cycles of operation is rotated at a high speed for extraction of the wash water through its perforate sidewalls as is well known in the art.

The tub 10 is driven by a stub shaft 12 drivingly connected through a clutch mechanism (not shown) to a drive motor (also not shown). An oscillating drive shaft 14 also extends from the drive motor and transmission through the axis of rotation of the tub 10 and shaft 12 and terminates at approximately the top oftub 10.

A drive hub 16 is attached, as will later by explained in detail, coaxially to the top of shaft 14 so as to impart the oscillating motion of shaft 14 to the agitator structure of the present invention.

Still referring to FIG. 1, it is seen that the agitator structure includes two agitators, namely an inner agitator l8 and an outer agitator 20, of similar structure, with the outer agitator 20 being generally a hollow enlarged and modified version of the inner agitator 18.

As such, each agitator, l8 and 20, includes a concave base portion, 22 and 24, with a centerpost 26 and 28, extending therefrom. Each centerpost has spiral ramps 30 and 32 (the preferred embodiment shown including 3 such ramps) extending radially therefrom in an ever decreasing width as they rise from the base portion along the outer surface of the centerpost, terminating a short distance from the top 34 and 36 of the centerpost. The outer edge of the ramp terminates in a generally vertical sidewall, 38 and 40, which itself terminates at either the base portion 22 and 24 or the following spiral ramp 30 and 32.

The sidewalls 40 of the outer agitator 20 also project vertically above the ramp 32 to form a raised rib or flange 42 which also initially projects vertically above the base portion 24 forming a vertical raised leading edge 44. The height of flange 42 above the ramp gradually decreases as it ascends from the base portion 24 along the ramp 32 so as to also terminate at the centerpost 28 a short distance below the top 36.

The inner agitator 18 also includes a rib or flange 46 which is generally a vertical extension of the sidewall 38 above the ramp 30. Flange 46 is much less pronounced than is the flange 42 of the outer agitator 20 and has a height that generally increases above the ramp 30 for a short distance as the ramp ascends from the base portion and then at a point generally midway up the ramp gradually decreases in height above the ramp so as to terminate prior to the point of termination of the ramp 30. The inner agitator also has additional fins 48 projecting radially outwardly from the sidewalls 38.

It is to be understood that the above-described agitators l8 and 20 are preferably molded of a plastic such as polypropylene and all surfaces such as the base portion 22 and 24, ramp 30 and 32, centerpost 26 and 28 etc., are integral with each other with the transition from one surface to the other being such that there are no well defined boundaries between them.

Also, it is to be understood that at least the centerpost 26 of agitator 18 is hollow for receiving drive shaft 14 and hub 16 in a telescoping manner and that the outer agitator 20 is also generally hollow and capable of receiving in a completely enclosed, nested arrangement the centerpost, ramps, fins and base of the inner agitator as describedlater.

The drive means for the agitators l8 and 20 is more fully disclosed in FIG. 2, and in referring thereto is seen to comprise the drive shaft 14, the drive hub 16, the centerpost 26 of the inner agitator 18 and centerpost 28 of the outer agitator 20.

The drive hub 16 comprises a generally solid cylindrical hub with an axial bore 52 having a flat or keyed face 54 for receiving a similarly keyed portion 56 of the drive shaft 14 in driving relationship. The periphery of the hub 16 defines a plurality of dovetail notches 58 having an inner arcuate face 60 of constant diameter and sidewalls 62 and 64 extending therefrom. The sidewalls 62 and 64 of each notch 58 converge downwardly and are further defined as being parallel to each other as viewed in a plane at right angles to the axis of rotation of the hub and also parallel to a line from the center of the hub to the midpoint of each arcuate face 60 for reasons to be explained.

The upper portion of the hollow centerpost 26 of the inner agitator 18 has means for mating with the hub 16 in driving engagement and also means similar to the hub structure for transmitting the drive to the outer agitator 20.

First, the hub mating means comprises dovetail lugs 66 projecting inwardly from the inner surface of the centerpost 26. Lugs 66 have sidewalls 68 and 70 tapered downwardly similar to walls 62 and 64 of notch 58 which meet in a generally rounded apex 72. Sidewalls 68 and 70 are also parallel to each other and to walls 62 and 64 as viewed in a plane at a right angle to the axis of rotation. The wedging engagement of the sidewalls 68 and 70 of lugs 66 with the walls 62 and 64 of the notch support the agitator 18 on the hub 16 and provide a driving engagement therewith.

The outer surface of centerpost 26 has a plurality of wedgeshaped notches 74 at the upper end thereof similar to notches 58 of hub 16 in that they have generally converging sidewalls 76 and 78 which are parallel in the same manner as sidewalls 62 and 64. i

The hollow centerpost 28 of outer agitator has interior wedge-shaped lugs 80 at its upper portion which also have converging walls 82 and 84 which are parallel when viewed in a plane at a right angle to the axis of rotation, similar to walls 68 and 70 of lugs 66 of the inner agitator. The walls 82 and 84 of lugs 80 are wedgingly received by the walls 76 and 78 of the notches 74 in the inner agitator 18 to support the outer agitator 20 thereon and provide a driving engagement means between the inner and outer agitator.

Referring to FIG. 3, a force vector diagram is shown to illustrate the forces developed at the mating parallel walls of the drive of hub 16 and inner agitator 18 the presently preferred drive and seating engagement above described.

Assuming the drive shaft 14 is driven in a clockwise direction a force F, normal to the drive engaging parallel walls is developed to drive the inner agitator 18 also in a clockwise direction. Force F can be resolved into its component forces R and T with R representing the radial component and T the tangential component which provides the actual driving force.

Thus it is seen that the radial force R is inward, and therefore compressive in nature, and eliminates any tendency for the polypropylene centerpost 26 of the inner agitator 18 to expand as a result of cold flow such as might be the case if the radial component were outward or expansive, which in turn would eventually lead to interference with the nesting engagement therewith of the outer agitator centerpost 28 and drive lugs 80.

As previously stated, the outer agitator 20 is generally hollow with the exception of the flanges 42 which, because of their thin wall construction, are solid. The inner agitator 18, being of the same general configuration, is able to be received within the hollow outer agitator 20 with the upper portion of the centerposts of the two agitators being in driving engagement as previously explained.

The ramps and flanges 46 of the inner agitator 18 are made substantially smaller than the outer agitator so as to easily fit therein and also so as to substantially decrease the nature of the washing action the inner agitator induces when used alone. Fins 48 projecting radially from sidewall 38 provide additional agitation which in conjunction with that agitation action provided by the ramps an overall gentle yet effective washing action is developed by the inner agitator 18.

The inner agitator 18, also having a generally hollow configuration for receiving the drive hub 16 and shaft 14 within the centerpost 26 has a bushing (not shown) secured at the lower end in axial alignment with the centerpost for receiving the shaft 12 and cooperating with the drive engaging means of the hub 16 and lugs 66 to maintain the inner agitator in proper axial alignment within the tub 10.

To maintain either the inner agitator alone, or both the inner agitator and outer agitator in nested relationship, on the drive shaft 14, the drive shaft is provided with a threaded bow at its upper end and in axial alignment therewith, for receiving a similarly threaded stud 88 which projects through apertures 90 and 92 in the tops 34, 36 of the agitator structure when in an assembled position. A cap member 94 is threadably received on the stud 88 and when screwed down to tightly engage the tops of the agitators, provides sufficient force to positively seat the agitators and maintain them in driving engagement. To remove either the outer or both agitators, the cap 94 is merely unscrewed and the agitator structure lifted u ward.

In the preferred embodiment, each agitator 18 an 20 has three spiral ramps and five engaging notches 74 with mating lugs 80. As it is necessary for the ramps 30 of the inner agitator 18 to directly underlie ramps 32 of the outer agitator for proper nesting relationship and also necessary for the notches 74 to be in alignment with the lugs 80, the preferred embodiment has only one position in which this proper alignment exists. This position is indicated by reference marks 96 on the base of the respective agitators (only one being shown) which provide a readily visual indicator for the necessary alignment.

Thus an agitator structure is provided that permits variable washing action commensurate with the type of fabric being laundered, and, it being recognized that the majority of the time normal agitation is desired, eliminates any storage problem by having the agitator inducing gentle washing action received and stored within the regular agitator in a nested relationship.

We claim as our invention:

1. Agitator structure for a washing machine comprising:

a drive shaft,

first agitator means for providing a relatively gentle washing action drivingly connected to said drive shaft,

second agitator means for providing a relatively turbulent washing action comprising a generally enlarged configuration of said first agitation means including a centerpost and ramp structure extending therefrom, said centerpost and ramp structure being hollow for receiving said first agitator therein in an enclosed nested relationship; and

interconnecting drive means for driving said second agitator means by said first agitator means.

2. The agitator structure of claim 1 wherein the interconnecting drive means comprises complimentary engaging surfaces formed in the respective centerpost portions of each of said agitator means.

3. The agitator structure of claim 3 wherein said complimentary engaging surfaces comprise generally V-shaped notches on the exterior of the centerpost of said first agitator means and generally V-shaped lugs on the interior of the hollow centerpost of said second agitator means.

4. A vertical axis clothes washing machine having an upstanding tub for receiving clothes, agitator structure for imparting the desired agitation motion to said clothes and drive means extending into said tub generally at the vertical axis of said tub and drivingly engaging said agitator structure, said agitator structure comprising;

a first agitator means for imparting a relatively gentle agitating motion;

a second agitator means for imparting a relatively turbulent agitating motion; said second agitator means being generally hollow and able to removably receive said first agitator means therewithin in nested relationship; and,

complimentary engaging means associated with said first and second agitator means for imparting the motion of said first agitator to said second agitator when in said nested relationship.

5. The structure of claim 4 wherein each of said first and second agitators generally includes a central post portion and said complimentary engaging means comprises generally V- shaped notches on the exterior of said post portion of said first agitator means for receiving generally V-shaped lugs on the interior of the hollow post portion of said second agitator. 

1. Agitator structure for a washing machine comprising: a drive shaft, first agitator means for providing a relatively gentle washing action drivingly connected to said drive shaft, second agitator means for providing a relatively turbulent washing action comprising a generally enlarged configuration of said first agitation means including a centerpost and ramp structure extending therefrom, said centerpost and ramp structure being hollow for receiving said first agitator therein in an enclosed nested relationship; and interconnecting drive means for driving said second agitator means by said first agitator means.
 2. The agitator structure of claim 1 wherein the interconnecting drive means comprises complimentary engaging surfaces formed in the respective centerpost portions of each of said agitator means.
 3. The agitator structure of claim 3 wherein said complimentary engaging surfaces comprise generally V-shaped notches on the exterior of the centerpost of said first agitator means and generally V-shaped lugs on the interior of the hollow centerpost of said second agitator means.
 4. A vertical axis clothes washing machine having an upstanding tub for receiving clothes, agitator structure for imparting the desired agitation motion to said clothes and drive means extending into said tub generally at the vertical axis of said tub and drivingly engaging said agitator structure, said agitator structure comprising; a first agitator means for imparting a relatively gentle agitating motion; a second agitator means for imparting a relatively turbulent agitating motion; said second agitator means being generally hollow and able to removably receive said first agitator means therewithin in nested relationship; and, complimentary engaging means associated with said first and second agitator means for imparting the motion of said first agitator to said second agitator when in said nested relationship.
 5. The structure of claim 4 wherein each of said first and second agitators generally includes a central post portion and said complimentary engaging means comprises generally V-shaped notches on the exterior of said post portion of said first agitator means for receiving generally V-shaped lugs on the interior of the hollow post portion of said second agitator. 